Enzymes are biological catalysts. Catalysts lower the activation energy for reactions. The lower the activation energy for a reaction, the faster the rate. Thus enzymes speed up reactions by lowering activation energy.
Answer:
1.
mRNA - Messenger RNA: Encodes amino acid sequence of a polypeptide.
tRNA - Transfer RNA: Brings amino acids to ribosomes during translation.
rRNA - Ribosomal RNA: With ribosomal proteins, makes up the ribosomes, the organelles that translate the mRNA.
2.
Transcription is the process by which DNA is copied (transcribed) to mRNA, which carries the information needed for protein synthesis. Transcription takes place in two broad steps. First, pre-messenger RNA is formed, with the involvement of RNA polymerase enzymes.
3.
During translation, which is the second major step in gene expression, the mRNA is "read" according to the genetic code, which relates the DNA sequence to the amino acid sequence in proteins. Each group of three bases in mRNA constitutes a codon, and each codon specifies a particular amino acid (hence, it is a triplet code). The mRNA sequence is thus used as a template to assemble—in order—the chain of amino acids that form a protein.
Explanation:
Answer:
The major structural difference between chromatin and chromosomes is that the latter are more organized and condensed.
Explanation:
Chromatin is genetic material packaged into a complex by special proteins (histones). That complex is in the form of uncoiled structures, so chromatin fibers are long and thin. Chromatin structure is permissive to DNA replication, transcription and recombination events.
On the other hand, chromosomes are highly condensed structures of genetic material that are formed just before the cell division.